Conventional solid panel doors for cabinets or room entry are formed of a central panel surrounded by wooden rails and stiles in the manner of a frame. The frame is glued together at the corners and conventionally engages the central panel by a mortise and tenon joint such as a tongue and groove arrangement. The door is held together by glueing the outside rails and stiles together at the corners to form the frame surrounding the central panel.
Doors formed as briefly noted above may be damaged by changes in humidity or temperature which cause expansion or contraction of the wood or wood products employed in frame and panel. Such expansion or contraction of the panels applies forces to the corner glue joints of the door which often causes cracking of the joints.
There are, of course, various ingeneous door structures of wood, metal, plastic and the like which may accommodate changes in temperature or humidity but which require the incorporation of complicated joinder devices commonly including gaskets and specially manufactured mating elements. In this respect there is noted prior U.S. Pat. Nos. 3,987,599; 4,741,136, for example.
In sofaras cabinet shops or the like are concerned there does not appear to have been a simple solution to the problem of corner cracking of solid panel doors. The present invention provides such a simple solution which may be readily incorporated in the manufacture of this type of door at minimum expense.